What was the 18th amendment and how did this act usher in a new level of lawlessness in the united states? who were two of the most famous crime bosses during this time? how we're their methods different?

I don't know who the crime bosses were, but the eighteenth amendment was the prohibition amendment which banned alcohol in the United States. This began a new era crime centered around alcohol smuggling. It was comparable to today's illegal dug industry.